Please do try these troubleshooting steps that may help.
- Start by doing a hard reboot, unplug the AC adapter then press and hold the power button for 20 seconds or until the laptop shuts down completely.
- If the same problem will persist do try connecting the laptop onto an external monitor and see if you'll get a display from it.
- If there's a display on the external monitor press then Windows key + P at the same time and select Computer Only then press Enter.
- But if there's still no display on the external monitor proceed with reseating the RAM's. Remove them all for couple of seconds then put them back in making sure everything is seated properly.